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Developer ToolsPaymaster APICore Methods

Core JSON-RPC Methods

The Paymaster API uses JSON-RPC, which is the standard for communicating with Ethereum-compatible nodes. Below are the key methods available:

pm_supported_tokens

Retrieves the list of ERC20 tokens supported by the Paymaster for gas payments along with pricing information.

Parameters:

  1. userOperation - A minimal UserOperation object with at least the sender field
  2. apiKey - Your API key from the AA Platform
  3. entryPoint - The EntryPoint contract address (typically 0x5FF137D4b0FDCD49DcA30c7CF57E578a026d2789)

Example Request:

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "pm_supported_tokens",
  "params": [
    {
      "sender": "0xAAWalletAddress",
      "nonce": "0x0",
      "initCode": "0x",
      "callData": "0x",
      "callGasLimit": "0x0",
      "verificationGasLimit": "0x0",
      "preVerificationGas": "0x0",
      "maxFeePerGas": "0x0",
      "maxPriorityFeePerGas": "0x0",
      "paymasterAndData": "0x",
      "signature": "0x"
    },
    "YOUR_API_KEY",
    "0x5FF137D4b0FDCD49DcA30c7CF57E578a026d2789"
  ]
}

Example Response:

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "freeGas": true,
    "native": { 
      "gas": "0x337dc", 
      "price": 1, 
      "decimals": 18, 
      "symbol": "NERO" 
    },
    "tokens": [
      {
        "type": "system",
        "token": "0xD5a6dcff7AC339A03f6964c315575bF65c3c6cF6",
        "symbol": "DAI",
        "decimals": 18,
        "price": 2.1
      },
      {
        "type": "custom",
        "token": "0x13DCf97b6B94bDA883492AB46d556E8919445876",
        "symbol": "TestToken",
        "decimals": 18,
        "price": 0.1
      }
    ]
  }
}

In this response:

  • freeGas indicates whether gas sponsorship (Type 0) is available
  • native provides information about the native token (NERO)
  • tokens lists all supported ERC20 tokens with their respective price ratios relative to NERO

pm_sponsor_userop

Signs a UserOperation with the Paymaster, adding the paymasterAndData field necessary for sponsored or token-paid transactions.

Parameters:

  1. userOperation - The complete UserOperation to be signed
  2. apiKey - Your API key from the AA Platform
  3. entryPoint - The EntryPoint contract address
  4. context - An object containing payment details:
    • type - Payment type (0 for sponsored, 1 for prepay, 2 for postpay)
    • token - ERC20 token address (required for types 1 and 2)

Example Request for Free Gas (Type 0):

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "pm_sponsor_userop",
  "params": [
    {
      "sender": "0xAAWalletAddress",
      "nonce": "0x0",
      "initCode": "0x",
      "callData": "0xCallData",
      "callGasLimit": "0x88b8",
      "verificationGasLimit": "0x33450",
      "preVerificationGas": "0xc350",
      "maxFeePerGas": "0x9502f900",
      "maxPriorityFeePerGas": "0x9502f900",
      "paymasterAndData": "0x",
      "signature": "0xUserSignature"
    },
    "YOUR_API_KEY",
    "0x5FF137D4b0FDCD49DcA30c7CF57E578a026d2789",
    {
      "type": 0
    }
  ]
}

Example Request for ERC20 Payment (Type 1):

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "pm_sponsor_userop",
  "params": [
    {
      "sender": "0xAAWalletAddress",
      "nonce": "0x0",
      "initCode": "0x",
      "callData": "0xCallData",
      "callGasLimit": "0x88b8",
      "verificationGasLimit": "0x33450",
      "preVerificationGas": "0xc350",
      "maxFeePerGas": "0x9502f900",
      "maxPriorityFeePerGas": "0x9502f900",
      "paymasterAndData": "0x",
      "signature": "0xUserSignature"
    },
    "YOUR_API_KEY",
    "0x5FF137D4b0FDCD49DcA30c7CF57E578a026d2789",
    {
      "type": 1,
      "token": "0xTokenAddress"
    }
  ]
}

Example Response:

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "sender": "0xAAWalletAddress",
    "nonce": "0x0",
    "initCode": "0x",
    "callData": "0xCallData",
    "callGasLimit": "0x88b8",
    "verificationGasLimit": "0x33450",
    "preVerificationGas": "0xc350",
    "maxFeePerGas": "0x9502f900",
    "maxPriorityFeePerGas": "0x9502f900",
    "paymasterAndData": "0xPaymasterAddress+EncodedData+PaymasterSignature",
    "signature": "0xUserSignature"
  }
}

pm_entrypoints

Get the EntryPoint addresss currently supported.

request:

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "pm_entrypoints",
  "params": [
      "entryPoint"
  ]
}

response:

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": [
    "0x5FF137D4b0FDCD49DcA30c7CF57E578a026d2789"
  ]
}
High LevelPayment Types